Childbirth weight has increased due to improved nutrition, but so has the size of the average woman, and I'm not talking BMI here! Unless you are talking 'large' as in over 10lbs for the baby there is little difference in the amount of pain a woman will experience due to the contractions. With regard to the bonding issue it could be argued in both ways. Epidurals reduce the production of the bodies natural painkillers, endorphins, so the woman does not then have the natural 'high' following labour and so in a positive and receptive state. Good for bonding. This arguement could be countered by the fact that the release of adrenalin will also cause endorphin levels to fall and so if a woman is terrified in labour due to pain it would cause her endorphins to reduce. Death is natural, but as it is the end of life, where bodily systems are failing and administering drugs is only going to lead to the same conclusion, it should not really be considered in the same argument as the normal physiological process as birth.